DE2320008A1 - CONDENSATION RESINS MADE FROM PHENOLS AND ALPHA, ALPHA'-DIHYDROXYDIISOPROPYLBENZENE - Google Patents

Description

Bayer Aktiengesellschaft

Central area of patents, trademarks and licenses

. 509 Leverkusen, Bayerwerk

1.8, April 1973

Condensation resins made from phenols and 06, ofr ^f -! Dihydroxydiisopropylbenzenes

The invention has new light-colored condensation resins made from phenols and α, α- · -dihydroxydiisopropylbenzenes and a process for their production to the object.

As is well known, phenols can be mixed with (&, <& '- dihydroxydiisopropylbenzenes zu Cijö ^ '- bis-HydroxyphenylJ-diisopropylbenzenes realize. This reaction is catalyzed with acids or carried out at an elevated temperature without a catalyst. in the the first pail contains mainly the highly crystalline, sparingly soluble p-alkylated phenols, whereas the second pail contains Resin-like solidifying, easily soluble isomer mixtures of a, a'-bis- (hydroxyphenyl) -diisopropylbenzenes. Both substance groups are suitable for the production of resoles and resites. The p-alkylated phenols give crystallizable, the isomer mixtures are resinous resoles which are easily miscible with other resins such as epoxy resins and polyester resins. When using these resols for coatings, for example Silver lacquers are obtained as stoving lacquers for metals. In order to achieve such a light color, however, it is necessary a preliminary purification of the crude bisphenols either by recrystallization or distillation.

The object of the invention is to provide a process for the preparation of the hydroxy compounds mentioned, whose

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Terfanrens products can be used for the production of resols with particularly high-quality properties without costly cleaning .

It has been found that propylbenz.olen in the reaction of phenols with 06 (X ^l -Dihydroxydiiso "or their analogous reactive derivatives obtained non-crystallizing, extremely bright resinous condensation products when the reaction is carried out at temperatures between about 70 and 27O ⁰ C in the presence of __. acids of phosphorus as catalysts.

These resins, due to their light color, can be used immediately, i. H. without cumbersome cleaning, for example by high vacuum distillation or treatment with decolorizing adsorbents, converted into resol resins of silver lacquer quality.

Surprisingly, the resole resins obtained from the products according to the invention have excellent flow properties, so that practically no craters are formed when baking paint films, as they usually occur when baking phenolic resins. In addition, the resistance of the coatings to Ohemi-. alkalis, such as organic acids and sulfur releasers, are unmatched.

The resol resins produced from the new condensation resins are therefore of a high quality previously unknown in this field on.

The resins according to the invention consist of isomer mixtures of C ^ a ^ -Ms-ChydroxyphenylJ-diisopropylbenzenes, 4-ring compounds and more highly condensed products of not exactly known structure, such as by distillation and gas chromatography Analysis has been proven. The sum of the two last-mentioned groups of substances makes between 30 and 60% by weight of the

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driving products. The phenolic content of the products Hydroxyl group is 6.2 - 8.5 wt .- #.

In GB patent specification 932 811 it has been proposed, in addition to a number of other acids, orthophosphoric acid as a catalyst for the production of <%, £ &'- bis (4-hy dr oxyphenyl) diisopropylbenzenes, ie pure p-alkylated bisphenols Phenol and C6.06 ^f -dihydroxydiisopropylbenzene should be used. The experiments described there were carried out either with ΒΡ, -ether at room temperature or with dry HCl gas at 10O ⁰ G. As our own experiments show that given in the patent specification temperature range of -10 mag (4-hydroxyphenyl) -diisopropylbenzolen be perfectly valid to + 150 ⁰ C for HCl gas as a catalyst for the production of pure a., ^R-bis 0G, not but for orthophosphoric acid. This catalyzes any rate above 70 ⁰ C is not more the formation of pure p-alkylated bisphenols, but by a completely different hard resins and not to be expected composition and structure. The patent also does not reveal the lightening effect of phosphoric acid when used under the conditions according to the invention.

Suitable starting materials for the production of the resins according to the invention are on the one hand phenols with at least two free o- or p-positions, such as phenol itself, o-, p-, m-cresol, m-isopropylphenol, 3,5-xylenol, 3,5 -Diisopropylphenol and mixtures of these compounds, on the other hand OC ₁ OC * -dihydroxyp-diisopropylbenzene, a, C% '- dihydroxy-m-diisopropylbenzene, tt-hydroxy-isopropyl-m- and -p-isopropylbenzene, m- and p-diisopropenylbenzene, oCjCC'-bis-methoxy-m- and -p-diisopropylbenzene or other alkoxy-diisopropylbenzenes, furthermore ring-substituted OCfOc ¹ -dihydroxydiisopropylbenzenes such as 3-isopropyl-ccot'-dihydroxy-m-diisopropylbenzene and mixtures of these compounds, in particular mixtures -Dihydroxy-m- and -p-diisopropylbenzene.

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Suitable catalysts are acids of phosphorus, for example orthophosphoric acid, metaphosphoric acid, pyrophosphoric acid, phosphorous acid and hypophosphorous acid. These acids are preferred. But are effective also phosphoric acids substituted with organic radicals such as Phenyl and alkyl phosphonic acids, also partially esterified Acids of phosphorus such as monophenyl phosphate, monocresyl phosphate and finally acid salts of phosphoric acids such as ammonium dihydrogen phosphate or sodium dihydrogen phosphate. The amount of catalyst can be between 0.01 and 10 wt .- ^, preferably 0, -05 and 5 wt .- #, based on the entire reaction mixture, be. The molar ratio of the reactants is not particularly critical, but the phenolic must be Partners are used in excess. The molar ratio of phenols to dihydroxydiisopropylbenzenes is about in the range from 4 r 1 to 1: 5: 1; you can go beyond that Choose ratios, but this complicates the work-up.

The reaction temperature is between 70 and 270 ° C, preferably between 80 and 22O ⁰ C.

Simple implementation of the process consists in that the reaction mixture either in the presence or boils under reflux after azeotropic distillation of the water of condensation. The response time is also not critical and is between 1 and 8, preferably 2 and 5 hours. The reaction can be carried out with or without a solvent are, and to protect against oxidation, it is expedient to work under an inert gas such as nitrogen.

After the condensation, the catalyst is usually neutralized, for example by adding an equivalent amount of sodium or potassium hydroxide solution. The isolation of the condensate

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Sationsharze is conveniently done by distilling off the excess phenol under reduced pressure. The resins can be used immediately for the manufacture of resoles as well of epoxy and polyester resins can still be used.

The preparation of resoles carried out by heating of the condensation resins of the invention in'einem alcohol having 1 to carbon atoms, with from 30 to follow to 35 aqueous formaldehyde or formaldehyde donors such as paraformaldehyde and an alkaline catalyst solution prepared or by heating the alcohol condensation resin solution Formaldehyde and a basic catalyst that can be added before or during heating.

The reaction temperature is 30 - 140 g, preferably at 50-117 ⁰ C.

The reaction time depends on the reaction temperature and the amount of catalyst. It is generally between about 10 minutes and 48 hours. The weight ratio of formaldehyde used (100%) to the condensation resin can be 1: 8 to 1: 1. Suitable catalysts are bases such as lithium hydroxide, potassium hydroxide, sodium hydroxide, Calcium hydroxide, ammonia, sodium hydroxide together with sodium formate, sodium and potassium carbonate, barium hydroxide and mixtures of any of these catalysts. The amount of catalyst can be between 0.01 to 2.5 mol per 350 g of the used Condensation resin.

Working up the reaction mixture is very simple. The reaction mixture is treated with a dilute acid such as Sulfuric acid, hydrochloric acid, phosphoric acid, benzoic acid, acetic acid or lactic acid neutralized and evaporated or after Adding water, the organic phase is separated off and evaporated to the desired viscosity in vacuo.

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2320003

The hardening of the resol to the reset takes place from a solution of the resol with or without the addition of epoxy resin (such as Epikote 1007 from Pa. Shell) in a typical lacquer carrier such as methanol, butanol, isobutanol, benzene / butanol, ethyl acetate, xylene or methyl ethyl ketone, which is applied as a thin film to a metal surface. The usual flow-promoting agents can be added to the solution. By heating to 100 - 3ÖÖ ° C, preferably at 120 - 20O ⁰ C, -, is obtained an insoluble coating, der'die hereinbefore specified properties. The curing can also be carried out in the presence of catalytic amounts of acids such as hydrochloric acid, phosphoric acid, oxalic acid, p-toluenesulfonic acid, boric acid or lactic acid. Curing in a mixture with melamine resins, polyester resins or polycarbonates with or without acid is possible. ·

A suitable resole resin can be obtained, for example, by the following method:

16.95 kg 49 $ aqueous sodium hydroxide solution at 60 - 70 ⁰ C dissolved in 97.1 kg 30 $ aqueous lOrmaldehydlösung. This solu- is · solution at 90 ⁰ C within 10 minutes to a solution of 72 kg condensation resin (# phenol OH, 7.5, prepared from a mixture of 60 parts of a, &'- dihydroxy-1,3-diisopropylbenzene and 40 parts of CCjOG'-dihydroxy-i _f 4-diisopropylbenzene and phenol in the presence of phosphoric acid) and 145.5 kg of butanol are pumped. The mixture is then stirred at 90-93 ° C. for a further 30 minutes. After cooling to about 40 ⁰ C is added a solution of 10.1 kg of concentrated phosphoric acid and 150 kg Wasaer, then at about 40 ⁰ C the layers are separated. The organic phase is washed with water and evaporated. Approx. 128 kg of resol resin are obtained, with a pesticide content of $ 63-70.

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The color numbers listed in the following examples are taken from the iodine scale and 50 follow solutions of the resins in n-butanol measured.

example 1

A mixture of 194 g (1 mol) of a, C £ ^r -dihydroxy ~ p-diisopropylbenzene, 1130 g (12 mol) of phenol and 4 g of metaphosphoric acid is melted under nitrogen and heated in such a way that the water of reaction is distilled off over a steam-heated reflux condenser. The elimination of water begins at an internal temperature of 125 ° C. It is at about 180-185 ° C, the reflux temperature of the; Phenol. After 6 hours of reaction time, from the beginning, the elimination of water to gerech-, net, are added 2 g of powdered sodium hydroxide, allowed to cool slightly and distilled after removing the reflux condenser, the excess phenol to an internal temperature of 210 ⁰ G under 10 Torr from . This gives 284 g of a pale hard resin which is slightly clouded by the salt content. The color number is 0; the phenolic OH content is $ 8.3.

Example 2

A mixture of 194 g (1 mol) of 0 ^ 00 -dihydroxy-m-diisopropylbenzene, 752 g (8 mol) of phenol and 4 g of pyrophosphoric acid is reacted analogously to Example 1 and worked up after adding 1.8 g of powdered sodium hydroxide. This gives 260 g of a cloudy, bright hard resin with a phenolic OH content of 7.3 i> and a color number of 0th

Example 3

A mixture of 136 g (0.7 mol) of ctjO ^ -dihydroxy-m-diisopropylbenzene, 58 g (0.3 mol) of OC ₁ QC -dihydroxy-p-diisopropylbenzene,

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752 g (8 mol) of phenol and 1.2 ml of 85% phosphoric acid implemented analogously to Example 1 for 4 hours. After adding 1.2 ml of concentrated sodium hydroxide solution, the excess phenol ' distilled off according to Example 1, the residue dissolved in chlorobenzene, the solution extracted with water, over sodium sulfate dried and evaporated. This gives 260 g of a clear, light-colored hard resin with a phenolic OH content of 7.6 9 & and a color number of 0.

A 50 g sample of the resin is distilled in a high vacuum. At 200-240 ° C / 0.04 Torr, 25 g of a fraction consisting of a mixture of isomers of (Χ ,, οο * -bis (hydroxyphenyl) -diisopropylbenzene go, at 240-320 ° C / 0.04 Torr 18 The residue is 6 g.

Example 4

A mixture of 116 g (0.6 mol) OC _t QC ^% -dihydroxy-m-diisopropylbenzene, 78 g (0.4 mol) p-di-OS-hydroxyisopropylbenzene, 940 g (10 mol) phenol and 4 g phosphorous acid is implemented according to Example 1 for 4 hours. After adding 2 g of powdered sodium hydroxide, the work-up is carried out as in Example 3. 284 g of a clear, pale hard resin with a phenolic OH content of 8.2 <fo and a color number of 0.-

Example 5

A mixture of 116 g (0.6 mol) <£, # - · -dihydroxy-m-diisopropyl- "benzene, 78 g (0.4 mol) a ^ a ^ -dihydroxy-p-diisopropylbenzene, 752 g (8 mol) of phenol and an aqueous hydrolyzate which has been obtained by pouring of 3 g of phosphorus trichloride in 10 g of ice is reacted and worked up analogously to example 4, to give 295 g of a clear, bright hard resin with a phenolic OH content of 8.5 i » and a color number of 0.

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Example 6

A mixture of 116 g (0.6 mol) oCOG'-dihydroxy-m-diisopropylbenzene, 78 g (0.4 mole) C & jO ^ -dihydroxy-p-diisopropy! Benzene, 752 g (8 mol) of phenol and 10 ml ¹ 85 #iger phosphoric acid is heated to an internal temperature under reduced pressure with stirring at 80 ⁰ C while the water of reaction is distilled off. After a reaction time of 2 hours, the water has been removed and a pressure of 25 torr has been reached. After a further 6 hours are 'one 8 _r 8 ml of concentrated sodium hydroxide solution and distilling the phenol to 210 G ⁰ at 10 Torr from. The residue is dissolved in toluene and the salt is filtered off with suction. After evaporation, 262 g of a clear, pale hard resin with a phenolic OH content of 7.5 and a color number of 0 are obtained.

A 50 g sample of the resin is distilled in a high vacuum. This gives 24.5 g of a fraction which passes over at 210-24O ° C./0.5 Torr and which consists of a mixture of isomers of OCfOC * -bis- (hydroxyphenyl) -dxisopropylbenzene, and 13.5 g of a fraction at 250-32Q ° C / 0.05 Torr distilling fraction and 11g undistillable residue.

Example 7

A mixture of 116 g (0.6 mol) as, Cfc ^r -dihydroxy-m-diisopropylbenzene, 78 g (0.4 mol) Oi, Ct ^f -dihydroxy-p-diisopropylbenzene, 756 g (7 mol) of an m- , p-cresol mixture 70:30 and 1.4 ml of 85% phosphoric acid is reacted according to Example 1 for 4 hours. Priority 1.23 ml of concentrated sodium hydroxide solution and the procedure is continued according to Example 1. This gives 262 g of a bright hard resin with a phenolic OH content of 6.3 $> and a Parbzahl of 0th

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Yo

Example 8 '

A mixture of 1250 g of phenol, 194 g of a mixture of 0C _t Gt * -dihydroxy-m- and -p-diisopropylbenzene in a ratio of 7-13 and 2 g of 85% phosphoric acid are heated with stirring and nitrogen. Compartment 2 hours, the water of reaction is distilled off azeotropically and a bottom temperature of 180 ⁰ C is reached, which is maintained for 2 hours. After cooling to approx. 100 ^° C., the mixture is neutralized with 4 g of 50% sodium hydroxide solution and excess phenol is distilled off. 260 g of yellowish condensation resin with a phenolic OEE content of 7.3 ° and an iodine color number of 2 are obtained.

Example 9

A mixture as in Example 8, but instead of phosphoric acid, 4 g of ammonium dihydrogen phosphate as a catalyst contains. The reaction is carried out as in Example 8 with the difference that 5 hours instead of 2 hours at 180 ° C can react. Work-up results in 23: 1 g light Condensation resin with an iodine color number of 2.

Example 10

If example 9 is repeated with diammonium hydrogen phosphate, then 235 g of light-colored condensation resin with an iodine color number are obtained Of 3.

Example 11

Example 9 is repeated, but with 2 g of hydrazine dihydrogen phosphate as a catalyst, 232 g of an almost are obtained colorless condensation resin with an iodine color number of 1. A 50 g sample of the resin is distilled in a high vacuum.

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JJ

5.2 g of a fraction passing over at 161-205 ° C./0.1 torr, 20.8 g of an isomer mixture of <x, C6 ^r -bis- (hydroxyphenyl) diisopropylbenzene (205-245 ° θ / θ, 1 Torr) and 24 g of residue.

Example 12 .

A mixture of 3 tons of phenol, 562 kg of a mixture of &, <& - dihydroxy-m- and -p-diisopropylbenzene in the ratio 3 ί 2 and 6.35 kg of 75% phosphoric acid are heated in the kettle with stirring and nitrogen. From 131 ^° C., water and phenol begin to distill azeotropically over a column. After 3 hours a temperature of -180 - 183 ° C is reached. About keeping 4 hours at this temperature, then cooled to about 100 ⁰ C, is 11.2 kg 50 follow caustic soda are added and destilliertbei 10 Torr excess phenol and increases the bottom temperature in the end with a low carrier gas flow briefly to 220 ⁰ C to distill off residual phenol. This gives 790 kg of a light yellow hard resin with a phenolic OH content of 8 ia and residual phenol content of <0.1 wt .- ^ and a Parbzahl of 2 (35 $ solution in butanol).

Comparative example 1

A mixture of 136 g (0.7 mol), of-dihydroxy-m-diisopropyl, 58 g (0.3 mol) β £, α -dihydroxy-p-diisopropyrbenzene, 940 g (10 mol) phenol and 1 , 5 g of p-toluenesulfonic acid is reacted analogously to Example 1. The elimination of water starts internal temperature at 135 ⁰ C. The reaction time is 6 hours. It is neutralized with 0.35 g of powdered sodium hydroxide and the excess phenol is removed by vacuum distillation. A completely opaque, chocolate-colored hard resin is obtained in an amount of 239 g.

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Comparative example 2

The previous experiment is repeated with the modification that instead of p-toluenesulphonic acid, 2Q g of an acidic active agent is used. fourth clay (Tonsil optimum) is used. One receives a pitch black hard resin in an amount of 235 g.

Comparative example 3

In 500 g of HCl gas-saturated phenol A solution of 194 ga "Cfc * -dihydroxy-p-diisopropylbenzene, registered in about 30 minutes and a further 4 hours under HGL-gassing at 80 ° C was maintained at 80 ⁰ C. After distilling off excess phenol remained 340 g of a brown crystalline residue, which consisted, according to gas-chromatographic analysis 92% of OC _r 6, a> ^f bis (4-hydroxyphenyl) -p-dilsopropylbenzol.

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Claims (6)

Claims A process for preparing a condensation product obtained by reacting phenols and <%, Oc: '- Dihydroxydiisopropylbenzolen or their analogous reactive derivatives in the presence of acidic catalysts, characterized in that the catalysts used are acids wipe of phosphorus at temperatures "used about 70 and 27O ⁰ C . 2) The method according to claim 1, characterized in that one ^{uses as 06, Ct f} -dihydroxydiisopropylbenzenes mixtures of OC ₁ QC -dihydroxy -m-diisopropylbenzene and c &, 0 £ '-dihydroxy-p-diisopropylbenzene. 3) Method according to claim 2, characterized in that the _r-mentioned dihydroxy compounds in a molar ratio 7: 3 to 3 employing ί. 7 4) Method according to claim 1 to 3> characterized in that that phenol itself, o-, m- and p-cresol or mixtures of these phenols are used as phenols. 5) Process according to claim 1 to 4, characterized in that the catalysts used are phosphoric acid or phoaphorige Acid used. 6) Condensation resins made from phenol and O ^ ce'-dihydroxydiisopropylbenzenes having a phenolic hydroxyl group content of 6.2 to 8.5% by weight, obtained by the process of claims 1 to 5. Le A 14 994 - 13 - 409845/1041